Influenza respiratory infection may be severe in children with chronic lung disease. Therefore, U.S.P.H. recommends children <6 mo. with lung disease be immunized ea. yr. In 1985-86 a pilot study of 19 children with BPD <18 mo. immunized last yr. suggested that serconversion rates are low. A larger group is needed to document this is to provide better immunization schedules and dosage.